i18n: Fix the chinese name of chinese language

The current version of chinese language's chinese name is not political neutral.
In fact, which form of chinese (traditional or simplified) can be called "正體"(in traditional chinese) or "正体"(in simplified chinese) is not globally defined.
So, I change the name according to the word used by Microsoft Windows, which is more neutral.
Switch from Rake to Paver
Change `if not args.skip_collect` to `if args.collect`

Simpler and clearer
from __future__ import print_function

and print errors and warnings to sys.stderr
write_stderr() function is unnecessary
Pull Paver requirements out into a separate file
Insert *right* at the front
Changed str->unicode in common/djangoapps/utils/.

LMS-2436
Removing ipython from edx dependencies.

Ipython is not strictly required to run edx-platform. It can
be setup as part of Vagrant provision scripts, or manually
by each developer as required in specific cases.
Some more str->unicode fixes in instructor and courseware apps.

LMS-2429
Merge pull request #3047 from edx/valera/add_ipdb_requiement

Removing ipython from edx dependencies
Revert to older version of TinyMCE.

We had trouble with Cloudfront/hashed files and need more time
to investigate.
This reverts commit e8f53ac9dc6d8a1d9928787635c7c5f7e409a9ec.
Merge pull request #3048 from louyihua/master

Make emails in lms translatable
Documentation for static page changes

STUD-1347
Merge pull request #3067 from edx/christina/revert_tinymce

Revert to older version of TinyMCE.
Merge pull request #3005 from singingwolfboy/db/paver

Paver v3
Merge pull request #2928 from edx/markhoeber/documentation/stud-1347

Documentation for changes to static pages
Merge pull request #3070 from edx/adam/middleware

wiki middleware fix (LMS-2461)
Concept added to Studio advanced components
Help paver find the theme directory